1. Field of the Invention
This invention relates to optical coupling and in particular to an optical slip ring for providing optical communication between rotating members.
2. Description of the Invention
Conventional slip ring assemblies are employed to achieve a continuous electrical connection between a rotor and a stator. In marine seismic exploration, (the application of this preferred embodiment) such slip rings are used to transfer data signals between an on-reel data source and a stationary reel housing. This arrangement permits the continuous transfer of data signals for any reel position desired.
In the prior art, friction contacts were employed and capacitive coupling was employed for such slip ring assemblies. For friction contact slip rings, problems such as excessive wear, contact bounce, and mechanical complexity create special difficulties. In the case of capacitive coupled slip rings, noise susceptibility and lack of DC coupling are prominent problems.
The present invention overcomes these problems. In addition to being highly noise resistant, the optical slip ring provides for direct DC coupling of the data signals. Also, the optical slip ring eliminates the wear and bounce problems encountered in the use of contact slip rings. The optical slip ring permits continuous transmission of high frequency digital information.